SNAKES OF THE GENUS PITUOPHIS 43 



and the length of the interspaces between them and show, in addition, 

 a marked average difference in the number of ventrals and the propor- 

 tionate tail length. Although only two localities are known for jani, 

 it is probable that it has a range contiguous with that of deppei, and 

 that a large series of specimens would show an area of intergradation 

 between the two forms. 



Diagnosis. — This form may be distinguished from P. d. deppei only 

 by the smaller number of spots and the greater length of the inter- 

 spaces between them. In jani the number of spots on body and tail 

 varies from 29 to 35, and the interspaces are at least 5 scales and gen- 

 erally more in length. In deppei the interspaces are usually less than 

 4 scales in length, but rarely 4, and the number of spots varies from 

 43 to 59. From lineaticollis, jani may be distinguished readily by the 

 lack of the continuous black dorsal stripes on the anterior part of the 

 body, which characterize the former species. Like the other two 

 forms of the deppei group, deppei and lineaticollis, jani differs from aU 

 other forms of the genus in having two supralabials on either side in 

 contact with the eye, rather than one, and two prefrontals present, 

 instead of four. 



IfiDescription. — The body of this form, as of the other members of 

 the deppei group, is slenderer than that of most other forms of the 

 genus, and the snout is blunt. The tail length forms from 0.120 to 

 0.141 of the total length (average 0.135). The longest specimen 

 examined measured 1,320 mm. 



The small number of specimens available renders a proper deter- 

 mination of the scale characters difficult, and the study of larger 

 series will undoubtedly greatly extend the range of variation in the 

 scale counts. On the basis of the limited number of specimens 

 examined the scutellation may be described as follows: Maximum 

 number of scale rows usually 29, occasionally 31; number of rows at 

 the neck 25-31, most frequently 27 (in 50 percent of the specimens 

 examined); number anterior to the vent 20 to 23, most often 21; 

 ventrals 225 to 235 (average 228.9); caudals 52 to 66 (average 62.4); 

 supralabials usually 8, sometimes 9, with the fourth and fifth or fifth 

 and sixth entering the eye; infralabials 10-13; a single preocular; 

 postoculars generally 3, occasionally 2 or 4; loreal present; no azygos 

 present between frontal and prefrontals ; rostral as broad as or broader 

 than long and penetrating at least one-third of the distance between 

 the internasals; frontal undivided. 



The dentition is as follows: Mandibular teeth 18 to 20, decreasing 

 slightly in size posteriorly; maxillary teeth 16 to 18, decreasing slightly 

 in size posteriorly; palatines 10, slightly smaller than the mandibular 

 and maxillary teeth; pterygoids 12 to 14, smaller than the palatines, 

 and decreasing in size posteriorly. 



136423 — 40 4 



